Seaside Crate

Every one of these carries something that would otherwise be sitting in a chest at the bottom of the sea, and that guarantee is the reason to fish here rather than anywhere else. They are Hardmode only, so before the Wall of Flesh the same spot produces Ocean Crates, and Shimmer will convert a Hardmode stack back down if you want that pool.

Water Walking Boots are the one worth waiting for, since they open the accessory chain that eventually ends in lava immunity. A Flipper and a Breathing Reed are convenience, handy if you never bothered with diving gear and redundant the moment you did. The Trident is a decent early spear and dead weight by Hardmode. An Inner Tube is a novelty.

Shark Bait rolls in its own slot, so it can come out alongside the guaranteed water chest item rather than replacing it. Shell Piles arrive in bulk for anyone building a beach, the Sandcastle Bucket is a toy, and Of Sea and Dreams rounds out the ocean paintings.

Metal comes as ore or as bars, from the early list or the Hardmode list, and a crate will not give you both tiers within the same category. Read those four rows as two draws and the haul stops looking as generous as the table suggests.

The ocean keeps producing these even after Corruption, Crimson or Hallow bleeds into it, so pushing the world into Hardmode does not cost you the fishing hole you set up. That makes it one of the few farm spots needing no upkeep and no cleanup once the spread starts.